Method of and apparatus for honing piston rings



1967 H. PHILIPPSEN ETAL 3,296,747

METHOD OF AND APPARATUS FOR HONING PISTON RINGS iii I x w FIG. 1

FIG. 2

/n ven tors Hans PH/L/PPSEN Theo MULLER 1967 H. PHILIPPSEN ETAL3,296,747

METHOD OF AND APPARATUS FOR HONING PISTON RINGS Filed Oct. 23, 1964 2Sheets-Sheet 2 7 g 4 Inventors Hans PH/L IPP SEN Th e 0 NULL ER y UnitedStates Patent M 3,296,747 METHOD OF AND APPARATUS FOR HONING PISTONRINGS Hans Philippsen, Opladen, and Theo Miiller, Pattscheid,

Germany, assignors to Goetzewerke Friedrich Goetze Aktiengesellschait,Dusseldorf, Germany Filed Oct. 23, 1964, Ser. No. 405,9il9 9 Claims.(Cl. 51-73) The present invention relates to a method of and apparatusfor honing self-clamping piston rings combined to a packet in a honingbushing which is held stationary during the honing operation.

According to heretofore known methods of the type involved, the workpiece packet was mounted on a mandrel and the thus obtained assembly wasintroduced into the honing bushing. After completion of the honingperiod, the mandrel, together with the machined piston rings, wasexchanged by hand for a mandrel with piston rings to be machined. Thecharging and discharging operation as well as the introduction andwithdrawal of the mandrels represented a time-consuming operation.

It is, therefore, an object of the present invention to provide a methodand apparatus for honing self-clamping piston rings combined to apacket, which will overcome the above mentioned drawbacks.

It is another object of this invention to provide a method of andapparatus for honing self-clamping piston rings combined to a packet, inwhich the manual introduction and withdrawal of the mandrel and themanual charging and discharging of the piston ring packets will beeliminated.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompany drawings, in which:

FIG. 1 is a side view of an apparatus according to the present inventionwith three pliers for respectively feeding and withdrawing the workpiece packets to and from a honing bushing.

FIG. 2 is a top view of a portion of the apparatus according to FIG. 1.

FIG. 3 is a side view of a modified apparatus according to the presentinvention with two honing bushings in which simultaneously one bushingis prepared for the honing operation while the other bushing is beingemployed for a honing operation.

FIG. 4 is a portion of a top view of FIG. 3.

The present invention is based on the finding that the inherent orinternal tension of self-resilient piston rings may be take advantage offor saving the mounting of such piston rings on mandrels. Accordingly,in conformity with the present invention, during the honing of the workpieces, the latter rest due to their inherent tension against the wallof the honing bushing supplied with a mixture of petroleum, oil andgrinding abrasive, and the work pieces are rotated and moved up and downbetween two rotating discs. The preferably plane end discs are in thehoning bushing moved together in conformity with a precisely defineddistance. The distance between said discs is so selected that the ringshave a low play toward both sides. Thus, the rings remain combined orcompacted to a package but nevertheless have a possibility of movementwhich is sufficient for the honing operation and for a radial engagementin the honing bush- 3 ,296,747 Patented Jan. 10, 1967 ing. Consequently,the discs, the diameter of which corresponds to that of the work pieces,convey their rotative movement during the alternating engagement withthe work pieces upon the ring packet to be honed.

For the sake of completeness, it may be mentioned that it has been knownheretofore to center work pieces to be honed by means of a honing tool.More specifically, to this end, the honing stones were introduced intothe bore of the work piece which was loosely mounted on the work piecetable, whereupon the honing stones were spread. However, the work pieceis clamped fast after the centering operation so that the saidheretofore known method concerns a mere preparation of the honingoperation but not the honing operation itself. For piston rings, onlythe above mentioned honing methods are known according to which the ringpacket is clamped on a mandrel and is moved in a honing bushing or isaxially clamped and machined by an outer honing broach. Over thisheretofore known method, the method according to the present inventionyields not only a considerably faster but also a more precise operation.

The efficiency of the method according to the present invention may befurther increased by so modifying the method that during a honingoperation, :a second work piece packet is prepared for honing while athird work piece packet, the honing of which has been completed, isbeing discharged. According to a further development of the presentinvention, each of the three packets may have associated therewith plieror jaw means which turn the respecive packet from a charging station toa honing bushing where it remains during the honing operation, whereassecond plier or jaw means is charged with a second packet, and thirdplier or jaw means releases the third honed packet whereupon the packetfollowing the honing operation is conveyed to a discharging station.

According to the present invention, the apparatus may also be sodesigned that it comprises one honing bushing each for holding the workpiece packet to be honed and for holding the work piece packet to beprepared for honing respectively.

Referring now to the drawings in detail and FIGS. 1 and 2 thereof inparticular, the arrangement shown therein comprises a machine frame 1having centrally mounted thereon a round indexing table 2, rotatable onan axis 2a, and carrying at a substantially even distance from eachother three jaws 3, 4 and 5 respectively. Mounted on frame 1 andlikewise arranged at a distance from each other there are arrangedaround table 2, a stand 6 with honing bushing 7, a charging station witha magazine 8, and a feeder 9, as well as a discharge station (FIG. 2)with an indexing table 10 having a plurality of receiving mandrels 11.

Pistons 12 in frame 1 and stand 6 move discs (13, 14 on one honingspindle each 13, 14' in honing bushing 7 from both sides against theworkpieces 15. The bushing 7 is supplied with a honing mixture 16.

Pistons 17 in the frame portion pertaining to the char-ging station movecarriage 9 into or withdraw the same from jaws 4 and lift the workpieces 15 out of or lower the same into the magazine 8.

The rings 15 to be honed are by means of carriage 9 moved in stacks frommagazine 8 into the then open jaws 4. When jaws 4 have thus beencharged, they close and press the work pieces 15 to a dimension suchthat the rings can be inserted in bushing 7. The jaws 4 are then bymeans of the indexing table 2 turned toward the honing station. Here,the ring packet is by means of honing spindle 13 pressed from the jawsresting on bushing 7 into the latter. The two discs 13, 14 willthereupon move toward each other in conformity with a predetermined andpreadjusted distance, which is so selected as to give the work pieces 15a slight axial play in honing bushing 7. During the now starting honingoperation, the ring packet is by means of honing spindles d3, 14 movedup and down in honing bushing 7, while a honing substance 16 is suppliedto said bushing. After the adjusted honing period has lapsed, the honedpacket 15 is by means of honing spindle 14 returned into the jaws andafter a further turning movement of the indexing table 2 is by openingsaid jaws discharged onto a receiving mandrel 11. The charging of jaws 4and discharging of jaws 5 is effected during the honing operation of thework pieces introduced into bushing 7 from jaws 3.

Bushing 7, during the honing operation, is oscillated or rotated bymotor M which drives a pinion 7 meshing with gear 7" on bushing 7 toprovide for relative rotating motion between the packet of rings and thebushings.

According to the modification illustrated in FIGS. 3 and 4, the jaws 3,4, 5 have been dispensed with. Instead, in addition to the honingbushing 7 there is provided a further honing bushing 7a which during thehoning operation in bushing 7 is discharged and recharged. Rings 15 tobe honed are by means of carriage 9 moved from magazine 8 eitherindividually or in packets into the tapered charging end of the emptyhoning bushing 7a and by means of a ram 18 pressed into the bushing.Thereupon, bushing 7a is turned toward the honing station and clampedfast. The two rotating honing spindles 13', 14' are now similar to thearrangement of FIGS. 1 and 2 moved toward each other in conformity witha predetermined distance from each other and from the work piece or workpiece packet 15. The subsequent honing operation, the return movementand discharging of bushing 7a is effected in the same manner asdescribed in connection with the embodiment of FIGS. 1 and 2. Prior tostarting the new charging operation, the punch 18 carries out a completestroke at which the honed rings are pressed upon a receiving mandrel 11of turntable 10. During the charging of the bushing 7a, the honingoperation takes place in bushing 7. Each bushing is, of course, rotatedduring the honing operation by suitable means such as are shown in thefirst modification.

It will be understood that discs 13, 14 could be rotated to produce therelative rotation between the packet of rings and the bushing, if sodesired. In such a case, motors M and M" could be provided drivingpinions 13" and 14" meshing with gears 13 and 14" slidably keyed to thespindles 13 and '14.

It is, of course, to be understood that the present invention is, by nomeans, limited to the articular arrangements described and shown in thedrawings but also comprises any modifications within the scope of theappended claims.

What is claimed is:

1. In an apparatus for honing split piston rings; a supply station forrings to be honed, a honing station comprising a honing bushing havingan internal diameter smaller than the free outer diameter of the ringsto be honed, and a discharge station for honed rings, means to conveyrings in the form of loose packets from said supply station to saidhoning station and from said honing station to said discharge station,and means in said honing station for reciprocating and rotating saidpacket of rings and bushing relatively to carrying out a honingoperation, the last mentioned said means in said honing stationincluding members adapted to be introduced into opposite ends of saidbushing for engagement with opposite ends of a packet of rings therein,and drive means connected to said members to drive said members inunison in the axial direction of said bushing.

2. In an apparatus for honing split piston rings, a supply station forrings to be honed, a honing station comprising a honing bushing havingan internal diameter smaller than the free outer diameter of the ringsto be honed, and a discharge station for honed rings, means to conveyrings in the form of loose packets from said supply station to saidhoning station and from said honing station to said discharge station,and means in said honing station for reciprocating and rotating saidpacket of rings and bushing relatively to carrying out a honingoperation, the last mentioned said means in said honing stationincluding members adapted to be introduced into opposite ends of saidbushing for engage merit with opposite ends of a packet of ringstherein, and drive means connected to said members to drive said membersin unison in the axial direction of said bushing, said means fortransferring rings from said supply station to said honing station andfrom said honing stat-ion to said discharge station comprising aturntable, jaw means on said turntable adapted to grasp packets of ringsand moveable by the turntable from station to station in succession, andmeans for moving packets of rings from said supply station into theadjacent said jaw means and from the jaw means adjacent said honingstation into said bushing and vice versa, and from the said jaw meansadjacent said discharge station into said discharge station.

3. In an apparatus for honing split piston rings; a supply station forrings to be honed, a honing station comprising a honing bushing havingan internal diameter smaller than the free outer diameter of the ringsto be honed, and a discharge station for honed rings, means to conveyrings in packets from said supply station to said honing station andfrom said honing station to said discharge station, and means in saidhoning station for reciprocating and rotating said rings and 'bushingrelatively to carrying out a honing operation, said means fortransferring rings from said supply station to said honing station andfrom said honing station to said discharge station comprising aturntable, and a plurality of honing bushings on said turntable moveablefrom station to station, means to supply rings from said supply stationto the adjacent bushing to form a packet therein to be conveyed in thebushing to the honing station, and means to discharge a packet of honedrings from the bushing adjacent said supply station to said dischargestation prior to supplying rings from said supply station to the saidbushing.

4. An apparatus according to claim 2 in which said discharge stationcomprises a turntable with a plurality of mandrels spaced thereabout,said mandrels being selectively alignable with the jaw means adjacentsaid discharge station by rotation of said turntable.

5. An apparatus according to claim 3 in which said discharge stationcomprises a turntable with a plurality of mandrels spaced thereabout,said mandrels being selectively alignable with the said bushing adjacentsaid discharge station by rotation of said turntable.

6. An apparatus according to claim 3 in which the said means in saidhoning station includes members adapted to be introduced into oppositeends of said bushing for engagement with opposite ends of a packet ofrings therein, and drive means connected to said members to drive saidmembers in unison in the axial direction of said bushing.

7. A method of honing loose packets of split piston rings whichcomprises; stacking rings to form a loose packet thereof, inserting theloose packet of the rings to be honed into a bushing having an internaldiameter smaller than the free outer diameter of said rings and a lengthgreater than the length of the packet of rings, supplying a honingcompound to the inside of the bushing, introducing separate members intosaid bushing from opposite ends thereof and engaging said packet ofrings in said bushing at opposite ends of the said packet by saidseparate memtbers, reciprocating said members in unison from outsidesaid bushing so as to reciprocate said packet of rings and bushingrelatively in the axial direction of the bushing, and relativelyrotating said bushing and members during said relative reciprocation tocause relative rotation of said packet of rings and said bushing.

8. The method according to claim 7 which includes the step of forming asecond loose packet of rings to be honed simultaneously with the honingof previously formed packet of rings.

9. The method according to claim 8 which includes the step ofsimultaneously forming a loose packet of rings to be honed whiledischarging a honed loose packet of rings while honing still anotherloose packet of rings.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS4/1957 Germany.

HAROLD D. WHITEHEAD, Primary Examiner.

L. S. SELMAN, Assistant Examiner.

1. IN AN APPARATUS FOR HONING SPLIT PISTON RINGS; A SUPPLY STATION FORRINGS TO BE HONED, A HONING STATION COMPRISING A HONING BUSHING HAVINGAN INTERNAL DIAMETER SMALLER THAN THE FREE OUTER DIAMETER OF THE RINGSTO BE HONED, AND A DISCHARGE STATION FOR HONED RINGS, MEANS TO CONVEYRINGS IN THE FORM OF LOOSE PACKETS FROM SAID SUPPLY STATION TO SAIDHONING STATION AND FROM SAID HONING STATION TO SAID DISCHARGE STATION,AND MEANS IN SAID HONING STATION FOR RECIPROCATING AND ROTATING SAIDPACKET OF RINGS AND BUSHING RELATIVELY TO CARRYING OUT A HONINGOPERATION, THE LAST MENTIONED SAID MEANS IN SAID HONING STATIONINCLUDING MEMBERS ADAPTED TO BE INTRODUCED INTO OPPOSITE ENDS OF SAIDBUSHING FOR ENGAGEMENT WITH OPPOSITE ENDS OF A PACKET OF RINGS THEREIN,AND DRIVE MEANS CONNECTED TO SAID MEMBERS TO DRIVE SAID MEMBERS INUNISON IN THE AXIAL DIRECTION OF SAID BUSHING.